Studies on a Calanus Patch II. The estimation of algal productive rates

1963 ◽  
Vol 43 (2) ◽  
pp. 339-347 ◽  
Author(s):  
D. H. Cushing
Keyword(s):  
Primary Productivity ◽  
Unit Volume ◽  
Standing Stock ◽  
Single Species ◽  
Algal Community ◽  
Division Rate ◽  
Common Experience ◽  
Unit Surface ◽  
The Common ◽  
Algal Material

Algal productive rates have rarely been estimated at sea, although many estimates have been made of primary productivity as g carbon/m2/day. A distinction may be drawn between productive rate and productivity, and it is in the use of the term ‘standing stock’. The latter is the quantity of living algal material per unit volume or beneath unit surface. The productive rate is the rate at which the standing stock reproduces itself; for a given species it is of course a division rate. It is expedient to use the term ‘division rate’ for a single species, but the term ‘productive rate’ may be used for the whole algal community. The productivity is the product of standing stock and productive rate and so contains in it the very great variations of standing stock that are the common experience of all planktologists.

scholarly journals More Irrigated Crop Production with Less Water Use

2019 ◽  
pp. 218-226
Author(s):  
Ahmed Ibrahim Ekhmaj ◽  
Younes Daw Ezlit ◽  
Mukhtar Mahmud Elaalem
Keyword(s):  
Crop Yield ◽  
Irrigation Water ◽  
Performance Indicators ◽  
Unit Volume ◽  
Unit Area ◽  
Irrigation Management ◽  
Agricultural Practices ◽  
Common Practices ◽  
The Common ◽  
Production Output

Three major performance indicators developed by the International Water Management Institute (IWMI, 1998) are used in this paper to evaluate the performance of the irrigated crops in the region according to the commonly followed practices among farmers as compared with their performance under conditions of much improved irrigation management and agricultural practices. These indicators include the Standardized Gross Value Production (SGVP), the unit area production output (crop yield or its financial value per hectare) and the unit volume of irrigation water production output (crop yield or its financial value per cubic meter). The comparison between the two agricultural practices indicated that the unit area output of the common practices among farmers did not exceed 6483 Libyan Dinars / hectare, while that under the improved practices was 11605 Libyan Dinars / hectare. The unit volume of irrigation water output for the common practices was 0.63 Libyan Dinar / cubic meter, while that under the improved practices reached 1.63 Libyan Dinar / cubic meter. These results clearly show the importance of the applied performance indicators in the assessment and clarification of the economic impacts of any introduced interventions aiming at the improvement of and/or the differentiation among irrigation management practices and alternative agricultural cropping systems.

scholarly journals Does the vicinity of the Black-Headed Gull colony (Chroicocephalus ridibundus) increase the breeding success of the Common Tern (Sterna hirundo) on the islands of the middle Vistula?

2018 ◽  
Vol 16 (4) ◽  
pp. 43-50
Author(s):  
Dariusz Bukackiński ◽  
Monika Bukacińska ◽  
Milena Grabowska
Keyword(s):  
Hatching Success ◽  
Single Species ◽  
Common Tern ◽  
Egg Mass ◽  
Chick Survival ◽  
Effective Protection ◽  
Vistula River ◽  
Nesting Site ◽  
The Common ◽  
The City

We conducted our study in the Common Tern colony (STH) located on an island in the middle Vistula River course, at the height of the city of Dęblin (km 393–394 of the waterway), in 2017. Our goal was to investigate some aspects of the biology and reproductive ecology of this species. Due to the fact that STH breeds both in single-species as well as in two- or multi-species colonies, in associations with Little Terns (Sternula albifrons), Black-Headed Gulls (Chroicocephalus ridibundus) (LAR) and/or Mew Gulls (Larus canus), we wanted to investigate whether the neighborhood of other species (in this case LAR) affected hatching success and chick survival in STH. Our results clearly show that the presence of breeding terns in the neighborhood of the LAR colony was not accidental and/or caused by the lack of space on the island and/or the possibility of nesting elsewhere. The height of nesting site, type of nesting habitat, clutch size, mean egg volume and mean egg mass of these STH pairs did not differ significantly from those that formed a single species colony, on the same island but several hundred meters away. However, STH nests in the neighborhood of the LAR colony were established much earlier and both the hatching success and chick survival of STH during the early-chick stage were twice as high. Thus, we can conclude that the LAR colony could provide an effective protection against predation of crows, magpies and gulls, dangers which accounted for the vast majority of STH nest failures in the year of our study.

Accommodations

Outsiders ◽  
2019 ◽  
pp. 111-134
Author(s):  
Zachary Kramer
Keyword(s):  
Civil Rights ◽  
Status Quo ◽  
Meaningful Change ◽  
Common Experience ◽  
Exchange Of Information ◽  
The Status ◽  
The Common ◽  
The Right ◽  
Vexing Problem

Accommodations are a common feature of life, but a vexing problem in civil rights law. To accommodate is to disrupt the status quo, to regard another, to recognize one’s needs and humanity. Accommodations can be a powerful thing. Even brief accommodations are an exchange of information, which become crucial experiences, as they force us to reckon with a harsh truth: The idea that all people are created equal is a legal command, not a practical description. We all have different needs and capabilities, different beliefs and wants. We accommodate not to erase these differences but to respect them. As a vehicle to realize our ambitions, and a functional means to make equality real for everyone in need of respect, accommodations are a way to bring outsiders in. As a result, accommodation is the antidote to modern discrimination. As we turn inward, as individuality becomes the common experience, accommodation is the right tool for our time. It is a means of making meaningful change.

La naturaleza dada. Hacia una correcta hermenéutica de la naturaleza, y sus implicancias para el cuidado de la casa común

2016 ◽  
Vol 65 (6) ◽  
Author(s):  
Alejandro Serani Merlo
Keyword(s):  
Future Generations ◽  
Know How ◽  
Common Experience ◽  
Human Subjectivity ◽  
The Future ◽  
The Common ◽  
Common Man ◽  
Common House ◽  
Practical Field ◽  
Economics And Politics

La conciencia actual de que estamos haciendo inhabitable la “casa común” para las futuras generaciones, tiene raíces objetivas y subjetivas. Subjetivamente el hombre de la calle percibe con angustia la destrucción de algo que ya no conoce y que no sabe cómo cuidar. La modernidad, con su división entre la res extensa y la res cogitans, condujo a una disociación entre la idea de naturaleza que tiene el hombre común, y la idea docta de naturaleza. Las ontologías doctas de corte materialista o idealista hacen depender la naturaleza de la subjetividad humana, mientras que la experiencia espontánea reconoce en ella una existencia “dada”. Se proponen tres sentidos de “lo dado” que permiten hacerse cargo filosóficamente de la experiencia común. Nos parece imperativo recuperar una concepción realista de la naturaleza que permita establecer límites objetivos a la técnica y a su lógica, que tiende hoy a invadir, todo el ámbito de lo práctico, incluidas la economía y la política. ---------- The current awareness that we are making uninhabitable our “common house” for the future generations has both objective and subjective roots. Subjectively, the common man anxiously perceives the destruction of something that no longer understands and who does not know how to care. With its division among res extensa and res cogitans, modernity leads to dissociation between the common idea of nature and the academic one. The erudite materialistic or idealistic ontologies make depend “nature” from human subjectivity, while, on the contrary, with spontaneous experience we should recognize to it a “given” existence. We suggest here three meanings of the term “given” that allow us to face in a philosophical sense our common experience. It seems necessary to recover a realistic conception of nature that aims to establish objective limits to technique and its logic, which now tends to invade the entire “practical field”, including economics and politics.

scholarly journals Environmental variation mediates the prevalence and co-occurrence of parasites in the common lizard, Zootoca vivipara

BMC Ecology ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Qiang Wu ◽  
Murielle Richard ◽  
Alexis Rutschmann ◽  
Donald B. Miles ◽  
Jean Clobert
Keyword(s):  
Environmental Factors ◽  
Human Disturbance ◽  
Vegetation Cover ◽  
Structural Equation ◽  
Environmental Gradients ◽  
Parasite Load ◽  
Single Species ◽  
Common Lizard ◽  
Zootoca Vivipara ◽  
The Common

Abstract Background Hosts and their parasites are under reciprocal selection, leading to coevolution. However, parasites depend not only on a host, but also on the host’s environment. In addition, a single host species is rarely infested by a single species of parasite and often supports multiple species (i.e., multi-infestation). Although the arms race between a parasite and its host has been well studied, few data are available on how environmental conditions may influence the process leading to multiple infestations. In this study, we examine whether: (1) environmental factors including altitude, temperature, vegetation cover, human disturbance, and grazing by livestock affect the prevalence of two types of ectoparasites, mites and ticks, on their host (the common lizard, Zootoca vivipara) and (2) competition is evident between mites and ticks. Results We found the probability of mite infestation increased with altitude and vegetation cover, but decreased with human disturbance and presence of livestock. In contrast, the probability of tick infestation was inversely associated with the same factors. Individuals with low body condition and males had higher mite loads. However, this pattern was not evident for tick loads. The results from a structural equation model revealed that mites and ticks indirectly and negatively affected each other’s infestation probability through an interaction involving the environmental context. We detected a direct negative association between mites and ticks only when considering estimates of parasite load. This suggests that both mites and ticks could attach to the same host, but once they start to accumulate, only one of them takes advantage. Conclusion The environment of hosts has a strong effect on infestation probabilities and parasite loads of mites and ticks. Autecological differences between mites and ticks, as indicated by their opposing patterns along environmental gradients, may explain the pattern of weak contemporary interspecific competition. Our findings emphasize the importance of including environmental factors and the natural history of each parasite species in studies of host–parasite coevolution.

1. Note on Ångström's Method for the Conductivity of Bars

1875 ◽  
Vol 8 ◽  
pp. 55-61 ◽  
Author(s):  
Tait
Keyword(s):  
Thermal Conductivity ◽  
Unit Volume ◽  
Transverse Section ◽  
Unit Surface ◽  
Image Position ◽  
Quantity Of Heat

If we assume the excess of temperature above that of the air, v, to be the same throughout a transverse section of the bar, the equation for the flux of heat is—where cρ is the water equivalent of unit volume of the bar, k its thermal conductivity, a its side, and hv the quantity of heat lost by radiation and convection from unit surface of the bar per unit of time, when the excess of temperature is v.

Withdrawal from Sport and Schlossberg’s Model of Transitions

1991 ◽  
Vol 8 (2) ◽  
pp. 152-160 ◽  
Author(s):  
Derek A. Swain
Keyword(s):  
Career Change ◽  
Horse Racing ◽  
Common Experience ◽  
Transitional Experience ◽  
Personal Histories ◽  
The Common ◽  
The Individual ◽  
Changes Over Time ◽  
Depth Interviews ◽  
Over Time

The present study involved three in-depth interviews with 10 informants who had voluntarily withdrawn from hockey, horse racing, football, and racquet-ball. The personal histories of the informants were examined for diversity and commonality of experience. A synthesized description of career change experience was written as a general story, identifying a sequence of experiential units that reflect the shifts in focus within the common experience. The general story indicated that withdrawal from sport was not simply an event but a process that began soon after the athletes became engaged in their career. This study supports and extends a model proposed by Schlossberg (1984) which attempts to account for diversity in the experience of transitions. The model is considered helpful in developing an understanding of the process of a transitional experience such as retirement from sport, considering the context in which the experience takes place, the meaning it has for the individual, and how it changes over time.

Visitors to Heritage Sites

2016 ◽  
Vol 56 (1) ◽  
pp. 67-80 ◽  
Author(s):  
Thu Thi Trinh ◽  
Chris Ryan
Keyword(s):  
New Zealand ◽  
Textual Analysis ◽  
Physical Characteristics ◽  
Common Experience ◽  
Heritage Sites ◽  
The Common ◽  
Similarities And Differences

Any tourist evaluation of place is partly shaped by the tourist’s own culture, and this may be even more so when the site gazed upon is representative of a different culture and/or heritage. However, this article suggests that differences of evaluations may be overemphasized if the research concentrates solely on the variable of nationality. The physical characteristics of place, the interpretation offered, and possibly other features such as the level of crowding all have a role to play. The common experience of these factors by tourists of different nationalities may create a commonality of evaluation despite differences in tourists’ cultures. The study reported here of more than 200 respondents uses textual analysis to find similarities and differences between Australian, Chinese, German, and New Zealand visitors to a Maori cultural site in New Zealand.

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